This notice invites you to file your return because you have money in your account. This Notice is similar to Notice CP80. It implies that you will get a refund if you file. It is true that if you do not file your return within the 3 year time period, you lose the refund and you don't get an offset against other taxes you may owe.
However, it is important not to over-react. Depending on the facts & time periods involved it is not wise to rush out and file a return before reviewing your IRS information and considering your options. Especially since the IRS may seize your refund to pay for other taxes or student loans, etc.
Steps for Notice CP81
You should call the IRS at 1-800-829-1040 & order your Account Transcripts for all time periods (before & after the year in question) & your Wage & Income Transcripts for the IRS information. Please follow the Prep Steps & contact our Tax Attorney for a confidential consultation.